From a DOJ press conference today:
"In addition to the actions we have detailed, one of the defendants is also charged with illegally obtaining access to the supervisory control and data acquisition system of the Bowman Dam in Rye, New York. At the time of his alleged intrusion, the dam was undergoing maintenance and had been disconnected from the system. But for that fact, that access would have given him the ability to control water levels and flow rates – an outcome that could have posed a clear danger to the public health and safety of Americans. I would like to thank the Department of Homeland Security and the city of Rye, New York, for their assistance in managing this incident."